A quick guide to leg ulcers
Professor Carolina Weller Research Director NHMRC TRIP Fellow School of Nursing and Midwifery, Monash University
Leg ulcers are one of the more challenging clinical problems that confront health professionals in Nursing Homes (NH) as well as in hospitals. Clinicians are often presented with difficult-to-heal chronic wounds of unclear aetiology. In order to ensure timely healing outcomes, it is important to establish the cause of ulceration and assess for other contributing factors before embarking on treatment. The aim of treatment is to correct the underlying cause and optimise the state of the wound bed.
This case brings to our attention the importance of timely assessment, diagnosis and referral of older people who live in NH. It highlights the interplay of many important factors that need to be managed to ensure best practice outcomes for an older person and demonstrates that lack of clear documentation and communication leads to adverse events and untimely death. Non-healing in this case is related to inadequate assessment, lack of clear diagnosis, inadequate wound care, and delayed specialist referral.
Could a more thorough physical examination, communication and documentation of wound care practices and attempted treatments have aided a more accurate diagnosis in a shorter time frame? If we use the three principles of wound management as our best practice base: 1. Define the aetiology; 2. Control factors affecting healing; 3. Select appropriate local environmental management, we can highlight several deficiencies in the care of Mrs M from January to August.
1. Define aetiology: Initial ulcer evaluation to define the cause of the wound was lacking. Best practice would include a thorough history of presenting illness, medical history, and a review of systems with a goal of identifying complicating comorbid conditions that may be the cause of the initial wound.
A clinical examination can reveal systemic disease associated with cutaneous ulceration. Evaluation of the chronic ulcer including onset, presence of inciting trauma (possible initial pressure injury and PVD), progress of healing, history of similar lesions, wound location, and associated pain or exudate is paramount.
Helpful hints for assessment include:
Assess location, size, demarcation, and ulcer shape. Document if singular or multiple. Venous ulcers are commonly located in the gaiter area. Ulcers on the foot or high on the leg are unlikely to be venous. Arterial ulcers tend to be distal.
Assess wound edge, colour, wound bed characteristics, and the presence of undermining, satellites, or nodularity.
Document fibrinous, granulation, and necrotic tissue in wound bed (venous ulcers are not necrotic unless arterial disease coexists).
Evaluate lymph nodes and examine lower extremities for coolness or warmth.
Palpate dorsalis pedis and posterior tibialis pulses and evaluate peripheral sensation. Where possible, ABPI should be measured at the bedside.
Treat infection if wounds are purulent and feature spreading erythema and warmth, or pain is out of proportion to wound appearance.
Medications should be carefully reviewed as many may hinder healing or cause ulceration. For example, presentation of warfarin-induced necrosis includes petechial and ecchymosis to bullae and eventually eschar and ulceration over calf area.
2. Control factors affecting healing: Mrs M has several documented predisposing risk factors for developing wounds. She was elderly, malnourished, on long-term warfarin and had several chronic conditions. PVD and recurrent DVT history increased her risk of lower limb ulceration and the risk of pressure injury over bony prominences while bed bound. Wounds on the legs are slower to heal than elsewhere due to gravitational effects, less-than-optimal blood supply and vascular impairment. Mrs M had a history of ulcerative colitis which has been shown to predispose people to Pyoderma gangrenosum, which presents in a variety of guises and is easy to misdiagnose.
3. Select appropriate local environmental management (dressings). Necrotic tissue in the wound base indicates wound care is suboptimal. A dry wound bed will increase the risk of infection and delay healing. Inappropriate topical products (in this case Betadine) did not help her cause.
Investigations: Diagnostic tests should be chosen based on the history and physical examination and include obtaining a tissue biopsy specimen, cultures, hematologic laboratory analysis, vascular studies, and imaging.
Biopsy: can be useful to investigate specific skin pathology. It does not distinguish between, or diagnose, arterial or venous ulcers. However arterial and tissue analysis can diagnose infection, vasculitis or vasculopathy, inflammatory conditions, malignancy, and hypertensive ulcers.
Swabs for bacterial microscopy and culture: Chronic leg ulcers are colonised by bacteria (staphylococcus, pseudomonas). Swabs are therefore rarely helpful, but should be considered in ulcers complicated by recurrent episodes of cellulitis, resistant or painful ulcers, or if systemic symptoms such as fever are present.
Ankle brachial Pressure index (ABPI): Doppler ultrasound measurement of ABPI is the investigation most frequently used to identify arterial aetiology. However, results can be unreliable when ABPI is conducted by untrained health professionals and the test may be difficult to perform accurately in patients with severe oedema, very painful ulcers or extensive ulceration. Toe brachial pressure index (TBPI) may prove more accurate for identifying arterial perfusion in the feet and toes of patients with diabetes and renal disease.
Duplex ultrasound scan: Duplex ultrasound examination can visualise vessels and detect the velocity and direction of flow within the vessel. It is usually performed by a radiology or vascular department to assess the arterial system for blocks or narrowing. It also assesses the venous system for areas of incompetence or thromboses.
Blood tests: Other useful laboratory studies may include a complete blood cell count to evaluate for anaemia, and serum protein, albumin and zinc, to identify nutritional deficiencies.
KEY POINTS ASSESSMENT and DIAGNOSIS
A comprehensive assessment should include:
Clinical, pain and leg ulcer history
Examination of the person, the affected leg and the ulcerInvestigations to support diagnosis.
EARLY REFERRAL Refer patients with non-healing leg ulcers to specialist health professionals if there is:
Peripheral arterial disease indicated by an Ankle Brachial Pressure Index (ABPI) less than 0.8
Ulcers have not healed within three months
Antibiotic-resistant infected ulcers
Ulcers causing uncontrolled pain